Ever play a game that just feels nostalgic, like how replaying an old favorite felt? Every once in a while a game comes out that's clearly taken inspiration from one released before it. Sometimes a beloved series just never got to get as far as it could have, so someone else stepped in with a fresh new idea and made something really special.

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These sorts of games are known as spiritual successors. They're not actually sequels and don't even take place in the same universe (usually). However, the playstyle and tone of the two games are so similar that they feel like they're cut from the same cloth.

10 Undertale (To Mother And Earthbound)

Undertale Characters in a line

It's a rather well-known fact that the primary inspiration for Toby Fox's indie darling Undertale was Earthbound. The "Megalovania" track's initial incarnation was featured in an Earthbound fangame before it made its way to the webcomic Homestuck and then finally to its final form as boss music in Undertale.

What's not as well-known is that Earthbound was just a rebranded version of Mother 2, and Mother 3 had such a significantly different feel to it that it never made sense to make an Earthbound sequel out of it.

9 Dark Souls (To Demon's Souls)

Dark Souls Remastered logo

Dark Souls might have gotten the acclaim for its ridiculously hard boss fights that demand five hundred attempts before the player finally figures out how to get through them, but they were not the first. That would be Demon's Souls. The games are incredibly similar, with major emphasis put on boss fights and finding unique loot. Demon's Souls is actually a decent entry point for players wanting to try out the rhythm of the games and get some experience before failing at the other ones.

8 BioShock (To System Shock)

A big enemy in BioShock

System Shock was an amazing blend of horror and cyberpunk that explored life after death, extreme isolation, and the addicting changes of augmentation. However, it only made it to its second installment before the studio closed its doors.

BioShock came onto the scene almost a decade later, but still explored many of the same feelings as System Shock, even making a nod to the other games in its own title. Now BioShock is recognized as a powerhouse among FPS games. Fans can only imagine what could have been for System Shock if that series had continued.

7 Dragon Age (To Baldur's Gate)

Dragon Age Origins logo

One aspect that stood out to players when Dragon Age first came out was that it felt so much like the old Baldur's Gate games. All things considered, it's a logical comparison; BioWare even made two previous entries in the Baldur's Gate series before pivoting to their original IPs Dragon Age and Mass Effect.

While the interest and ability to make decent Baldur's Gate games has dwindled, Dragon Age is still going strong. The high fantasy RPG lets players experience the feeling of Dungeons and Dragons from the comfort of their screens instead of at a table, just like its spiritual predecessor Baldur's Gate.

6 Assassin's Creed (To Prince of Persia)

Assassin's Creed

What's that? One of the biggest modern game franchises is a spiritual successor to an older franchise that never went anywhere big even though it was fabulous? That's right. Assassin's Creed flourished after taking intense inspiration from Prince of Persia.

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The social stealth, the exploring around a town on many different levels, the battling between two factions, Assassin's Creedpicked it all up and ran away with it to become one of the most iconic series ever.

5 Call of Duty (To Medal of Honor: Allied Assault)

Call of Duty logos

Another massive franchise that's accrued much acclaim is Call of Duty. Once upon a time, however, it wasn't the wartime giant it is today. Initially, there was Medal of Honor: Allied Assault, a series that tried desperately to keep FPS game more or less realistic. When it all fell apart, Call of Duty was there to pick up the slack. They were initially so very similar that many fans actually thought they were one and the same!

4 Bloodstained: Ritual of the Night (To Castlevania)

Bloodstained Ritual of the Night logo

The legendary Castlevania naturally inspired many spiritual successors that borrowed various aspects of its gameplay, story, and worldbuilding. Numerous gothic-themed games have sprung from their love of the franchise, but it was Bloodstained: Ritual of Night that did it best.

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From the platform layout to the art style to the dark themes, Bloodstained captured all of the best parts of Castlevania and expanded upon it in its own world, truly doing its predecessor proud.

3 Bayonetta (To Devil May Cry)

Bayonetta logo

Have fun slaughtering demons and other monsters in Devil May Cry? Try it again in the Bayonetta series, this time as a female protagonist wearing funny clothes while cutting down ghouls.

These two franchises have such similar combat styles and rating systems after completed levels that they could have been easily made for each other. The only big difference is that Bayonetta is a lot less interesting in terms of plot. Win some, lose some.

2 Path of Exile (To Diablo II)

Path of Exile logo

One game that did better than the actual successor did was Path of Exile. Diablo II was a fabulous game and deserves every ounce of praise it gets, but when Diablo III came out, it was a major disappointment for fans who had been waiting years for a true sequel.

Path of Exile is everything Diablo III should have been — and then some. It's one of the most popular hack-em-slash-ems out there, and for good reason. The game has everything under its belt, from a fabulous story to solid mechanics, and years after release it's really become its own thing. Yet it still feels more like a Diablo game than Diablo III ever will.

1 Portal (To Half-Life)

Portal 2 game Title Art Jumping Through Portals

A little idea from outside sources was picked up by Valve and became the iconic puzzle game Portal. Valve even included some nods to their flagship Half-Life series, enough so that it's all but directly confirmed that the Portal series takes place in the same universe.

The game largely maintains the Half-Life aesthetic but expands upon it, using some of the physics-related tricks from the former to help design the most intense puzzles a player will ever encounter. But make sure to set aside plenty of time to get invested, because GLaDOS does something that makes it all but impossible to put the game down.

NEXT: 10 Ways Bleach Is Yu Yu Hakusho's Spiritual Successor